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TRANSACTIONS OF SOCIETIES. 



Chemical, Metallurgical and Mining Society of South Africa.— 

 Saturday, March 19th: A. McArthur Johnston, M.A., M.I.M.M., F.C.S., 

 President, in the chair. — " The Assay of Tin Ores " : J. Gray. The dry 

 assay and the wet analysis of tin ores were considered, and the view was 

 expressed that serious objection may be taken to every single step in the pro- 

 cedure for the dry assay of tin in ores, and even if the result obtained happened 

 to be correct, this was due to a balancing of errors. A method of wet analysis 

 was recommended, comprising fusion of the ore with sodium peroxide, extrac- 

 tion with water, treatment by means of Hydrochloric acid and iron reduction, 

 and, after neutralising, titration with iodine and starch. — " Mining at the 

 Redjang-Lebong Gold-Silver Mine, Sumatra " : H. Philp. A description 

 of the mine, and (jf the method adopted for working it, together with a few 

 remarks regarding the underground administration. 



South African Society of Civil Engineers. — Wednesday, .\pril 13th : 

 H. H. Elliott, A.M.I.C.E., President, in the chair. — " The Lighthouses of Cape 

 Colony" : H. C. Cooper. An account was given of the system of adminis- 

 tration of the Colony's lighthouses, of the means of illumination employed 

 at the several lighthouses, and of the equipment in particular of the 

 Robben Island, Green Point, and Cape Agulhas lights. The author considered 

 that, with few exceptions, the class of lighthouses was equal to that of the 

 most modern European types, and that when the recommendations of the 1906 

 Lighthouse Commission had been carried out the coast of Cape Colony would 

 be as well lit as any in the world. 



Royal Society of South Africa. — Wednesday, April 20th : S. S. Hough. 

 M.A., F.R.S., President, in the chair. — " Astronomy of precision " : S. S. 

 Hough (Presidential address). The author detailed some of the aims and 

 objects of modern astronomy, which rendered necessary the highest require- 

 ments of precise observation and physical measurement. He dealt with 

 certain unavoidable inaccuracies of observation, and passed on to consider 

 the validity of laws associating predicted with observed phenomena. The 

 author proceeded to discuss the motion of the solar system through space 

 and the means at disposal of estimating that motion, concluding with an 

 account of the methods in use at the Royal Observatory under his direction 

 for studying the radial velocities of stars, and discussing incidentally the 

 identification of the IMilky Way with the .second of Kapteyn's star drifts. 



ADDRESSES WANTED. 



The Assistant General Secretary (P.O. Box 1497, Cape Town) would be 

 glad to receive the correct addresses of the following members, whose last 

 known addresses are given below : — • 



Boulton, H. C, c/o Messrs. Pauling & Co., Ltd., Broken Hill, Rhodesia. 



Champion, Ivor Edward, P.O. Roberts Heights, Pretoria. 



Court, S. E., High Commissioner's Office, Johannesburg. 



Dickie, A., 475, Cnrrie Road, Durban, Natal. 



Durham, James, P.O. Box 2734, Johannesburg. 



Hutt, Ernest W., P.O. Box 2862, Johannesburg. 



Kessler, L., Mining Engineer, Rayton, Transvaal. 



Wilson, Allen, 37 and 38, Steytler's Buildings, Johannesburg. 



Zimmerman, J., P.O. Box 1743, Johannesburg. 



